The Dayco 17mm Bearing Steel Serpentine Idler / Tensioner Pulley is designed to deliver reliable, consistent performance. This pulley is constructed from steel and it offers a maximum belt width of 12 ribs, making it ideal for a variety of applications. This pulley is designed to provide long-lasting performance and is a great choice for keeping your Volvo/Mack running smoothly. FleetPride is your First Click in Heavy Duty®.